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171.
The current study aimed at evaluating the ability of a mineral and antioxidant-rich extract from Chondrus canaliculatus to improve maneb (MB)-induced toxicity in adult rat. The animals were divided into four groups: group 1 used as a control group, group 2 received MB, group 3 received MB + C. canaliculatus extract, and group 4 received only the algal extract. MB, a Mn-containing ethylene-bis-dithiocarbamate fungicide, induced oxidative stress damages, mineral perturbations in the plasma, urine, and bone, and genotoxicity in rats. Hematological analysis revealed in the MB-treated group a disruption in the number of red blood cells, platelets, and white blood cells associated with a striking genotoxicity. Interestingly, a significant increase in malondialdehyde and advanced oxidation protein product levels in erythrocytes and bones were found. On the other hand, an impairment of the antioxidant status in both tissues was occurred. Along, our results revealed that MB injection caused a striking drop and disruption in bone’s mineral rates, especially calcium and phosphorus. These biochemical results were in accordance with the histological and molecular changes. However, co-treatment with C. canaliculatus extract showed, for the first time, that this alga was effective against MB-induced hematotoxicity, genotoxicity, and oxidative stress in the blood and bone and maintained osteomineral metabolism and bone histo-architecture. Such observations might be explained by the strong in vitro antioxidant and antibacterial activities exhibited by the alga, as well as by its high levels in several minerals: calcium, phosphorus, sodium, potassium, magnesium, iron, and zinc.  相似文献   
172.
A polyphasic study was undertaken to establish the taxonomic status of three representative Geodermatophilus strains isolated from an extreme hyper-arid Atacama Desert soil. The strains, isolates B12T, B20 and B25, were found to have chemotaxonomic and morphological properties characteristic of the genus Geodermatophilus. The isolates shared a broad range of chemotaxonomic, cultural and physiological features, formed a well-supported branch in the Geodermatophilus 16S rRNA gene tree in which they were most closely associated with the type strain of Geodermatophilus obscurus. They were distinguished from the latter by BOX-PCR fingerprint patterns and by chemotaxonomic and other phenotypic properties. Average nucleotide identity, average amino acid identity and digital DNA–DNA hybridization values between the whole genome sequences of isolate B12T and G. obscurus DSM 43160T were 89.28%, 87.27% and 37.4%, respectively, metrics consistent with its classification as a separate species. On the basis of these data, it is proposed that the isolates be assigned to the genus Geodermatophilus as Geodermatophilus chilensis sp. nov. with isolate B12T (CECT 9483T = NCIMB 15089T) as the type strain. Analysis of the whole genome sequence of G. chilensis B12T with 5341 open reading frames and a genome size of 5.5 Mb highlighted genes and gene clusters that encode for properties relevant to its adaptation to extreme environmental conditions prevalent in extreme hyper-arid Atacama Desert soils.  相似文献   
173.
Surfactants play a very important role in laundry and household cleaning products ingredients. In this research, the application of lipopeptide biosurfactants, produced by Bacillus subtilis SPB1, in the formulation of a washing powder was investigated. The SPB1 biosurfactant was mixed with sodium tripolyphosphate as a builder and sodium sulfate as filler. The efficiency of the formulated detergent composition with different washing conditions to remove a stain from cotton fabric was examined. The results showed that the formulated detergent was effective in oil removal, with optimal washing conditions of pH, temperature, striate and time of washing system of 7, 65°C, 1000 RPM and 60 min, respectively. A comparative study of different detergent compositions (biosurfactant‐based detergent, combined biosurfactant‐commercial detergent, and a commercial detergent) for the removal of oil and tea stains, proved that the bio‐scouring was more effective (>75%) in terms of the stain removal than the commercial powders (<60%). Moreover, the results demonstrated that the biosurfactant acts additively with a commercial detergent and enhances their performance from 33 to 45% in removing oil stain and from 57 to 64% in removing tea stain. As a conclusion, in addition to the low toxicity and the high biodegradability of the microbial biosurfactants, the results of this study have shown that the future use of this lipopeptide biosurfactant as laundry detergent additive is highly promising.  相似文献   
174.
Orobanche foetida is a chlorophyll-lacking holoparasite that subsists on the roots of plants and causes significant damage to the culture of some leguminous plants particularly faba bean. To evaluate the effect of rhizobia as a biological agent and the effect of nitrogen (N) and/or phosphorus (P) to control O. foetida parasitism in faba bean (Vicia faba minor), a trial was conducted in infested and non-infested fields with O. foetida in the Oued Beja Agricultural Experimental Unit, Tunisia. This field trial was performed during two consecutive cropping seasons using the susceptible cv. Badï, two selected rhizobia strains (Bj1 and Mat) and N combined or not with P. Mat strain showed an antagonistic effect which displayed a parasitism index two-fold lower than the control and carried two times less of emerged parasite spikes at crop maturity. Seed-yield losses caused by O. foetida infestation were very high and reached 95% for the control. Despite this high reduction, faba bean inoculated with Mat strain showed an average yield three-fold higher than the control. Broomrape parasitism did not significantly affect the protein/starch ratio of seeds for all treatments. The Mat strain is a potential candidate for developing an integrate method to control O. foetida parasitism on faba bean.  相似文献   
175.
Many studies based on genetic diversity of North African populations have contributed to elucidate the modelling of the genetic landscape in this region. North Africa is considered as a distinct spatial‐temporal entity on geographic, archaeological, and historical grounds, which has undergone the influence of different human migrations along its shaping. For instance, Libya, a North African country, was first inhabited by Berbers and then colonized by a variety of ethnic groups like Phoenicians, Greeks, Romans, Arabs and, in recent times, Italians. In this study, we contribute to clarify the genetic variation of Libya and consequently, of North African modern populations, by the study of Libyan male lineages. A total of 22 Y‐chromosome‐specific SNPs were genotyped in a sample of 175 Libyan males, allowing the characterization of 18 Y‐chromosomal haplogroups. The obtained data revealed a predominant Northwest African component represented by haplogroup E‐M81 (33.7%) followed by J(xJ1a,J2)‐M304 (27.4%), which is postulated to have a Middle Eastern origin. The comparative study with other populations (~5,400 individuals from North Africa, Middle East, Sub‐Saharan Africa, and Europe) revealed a general genetic homogeneity among North African populations (FST = 5.3 %; P‐value < 0.0001). Overall, the Y‐haplogroup diversity in Libya and in North Africa is characterized by two genetic components. The first signature is typical of Berber‐speaking people (E‐M81), the autochthonous inhabitants, whereas the second is (J(xJ1a,J2)‐M304), originating from Arabic populations. This is in agreement with the hypothesis of an Arabic expansion from the Middle East, shaping the North African genetic landscape. Am J Phys Anthropol 157:242–251, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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177.
Zearalenone (ZEN) is a fusarotoxin produced mainly by Fusarium graminearum in temperate and warm countries. ZEN has several adverse effects on humans and animals. It has a strong estrogenic activity associated with hyperestrogenism and leads to several physiological alterations in the reproductive tract. Even though the mutagenic and genotoxic proprieties of ZEN have been described recently, its molecular mechanisms of action are not completely understood. The aim of this study was to determine the involvement of other possible mechanisms in ZEN-induced toxicities. Each of the following toxicities, cytotoxicity, cell cycle perturbation, genotoxicity, and mutagenicity, was monitored in Vero cells exposed to ZEN. Our results showed that ZEN-reduced cell viability correlated to cell cycle perturbation-induced DNA fragmentation, resulting in DNA-laddering patterns on agar gel electrophoresis. This observation is consistent with apoptosis, which was confirmed by induction of apoptotic bodies. Moreover, ZEN induced in a concentration-dependant manner the formation of micronuclei and chromosome aberrations. This apparent contradiction between the apoptotic and mutagenic effects of ZEN can be explained by the modification of normal cellular regulation inducing apoptotic or antiapoptotic factors resulting from a lack of or an incorrect DNA-reparation in relation to cell exposure to the toxin.  相似文献   
178.
Molecular Biology Reports - Matrix metalloproteinases (MMPs) are widely expressed in atherosclerosis lesions. The disequilibrium of MMPs driving to an overexpression or a lack of its level can be...  相似文献   
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180.

The fission yeast genus Schizosaccharomyces contains important model organisms for biological research. In particular, S. pombe is a widely used model eukaryote. So far little is known about the natural and artificial habitats of species in this genus. Finding out where S. pombe and other fission yeast species occur and how they live in their habitats can promote better understanding of their biology. Here we investigate in which substrates S. pombe, S. octosporus, S. osmophilus and S. japonicus are present. To this end about 2100 samples consisting of soil, tree sap fluxes, fresh fruit, dried fruit, honey, cacao beans, molasses and other substrates were analyzed. Effective isolation methods that allow efficient isolation of the above mentioned species were developed. Based on the frequency of isolating different fission yeast species in various substrates and on extensive literature survey, conclusions are drawn on their ecology. The results suggest that the primary habitat of S. pombe and S. octosporus is honeybee honey. Both species were also frequently detected on certain dried fruit like raisins, mango or pineapple to which they could be brought by the honey bees during ripening or during drying. While S. pombe was regularly isolated from grape mash and from fermented raw cacao beans S. octosporus was never isolated from fresh fruit. The main habitat of S. osmophilus seems to be solitary bee beebread. It was rarely isolated from raisins. S. japonicus was mainly found in forest substrates although it occurs on fruit and in fruit fermentations, too.

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